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T Juji

Publications and source records attributed to T Juji.

At least 109 records · Page 6Linked to original sources
PubMed1998

Crystallization and preliminary diffraction studies of the extracellular region of human p58 killer cell inhibitory receptor (KIR2).

Molecules of the human killer cell inhibitory receptor (KIR) family, which belong to the immunoglobulin superfamily (IgSF), are expressed on the surface of natural killer (NK) cells and some subsets of T cells. These receptors function to mediate the inhibition or activation of cytotoxic activity by recognizing HLA class I molecules on the target cell. The extracellular region of a p58 KIR specific for HLA-Cw1,3,7 (KIR2) has been overproduced in Escherichia coli and purified. The recombinant KIR2 has been crystallized in 9-10% poly(ethylene glycol) methyl ether (average Mr = 8000), 50mM HEPES, 8% ethylene glycol, 0.5% octyl-beta-glucoside, pH 7.5, at 294 K using the sitting-drop vapour-diffusion method. Preliminary X-ray diffraction studies reveal the space group to be hexagonal (P6122 or P6522) with lattice constants a = b = 95.3, c = 130.8 A. A native data set (3 A resolution) has been collected at the Photon Factory (lambda = 1.0 A).

Crystallization↗
PubMed1998

Dendritic cells stimulate the expansion of bcr-abl specific CD8+ T cells with cytotoxic activity against leukemic cells from patients with chronic myeloid leukemia.

The role of T lymphocytes in the control of chronic myeloid leukemia (CML) after bone marrow transplantations has been clearly shown. This effect closely correlates with graft-versus-host disease (GVHD). A specific graft-versus-leukemia (GVL) effect separate from GVHD has been postulated but has been difficult to show. One possible target for specific GVL activity is the bcr-abl fusion protein characteristic of CML. We have investigated the use of normal peptide-pulsed dendritic cells for the generation of cytotoxic, bcr-abl-specific T cells from normal donors. T cells (CD3+, CD8+, TCR alpha beta+, and NK receptor-negative) generated from a normal donor (HLA A24, B52, B59, Cw1) after stimulation with autologous dendritic cells, primed with a 16 mer peptide spanning the b3a2 breakpoint of bcr-abl, lysed CML cells from the peripheral blood of seven patients with CML with the b3a2 breakpoint. CML cells from four patients with only the b2a2 breakpoint were not lysed. Phytohemagglutinin (PHA) blasts derived from peripheral blood of patients with CML were not lysed, suggesting that cytotoxicity was not due to alloreactivity. Blocking experiments with anti-HLA-A,B,C indicated that cytotoxicity was dependent on recognition of major histocompatibility complex (MHC) class I molecules, although cytotoxicity was not MHC-restricted because not all patients shared HLA types with the T-cell donor. Specificity for bcr-abl and absence of alloreactivity was confirmed by the presence of lytic activity against autologous and allogeneic class I HLA-A matched monocytes pulsed with the 16 mer bcr-abl fusion peptide, but not against unpulsed monocytes or monocytes pulsed with other peptides. These results show that bcr-abl-specific T cells with marked cytotoxic activity against CML cells can be generated and amplified from normal donor peripheral blood. Recognition of HLA molecules is essential for cytotoxicity but strict HLA identity is not required.

Antigens↗
PubMed1998

Molecular cloning and characterization of decay-accelerating factor deficiency in Cromer blood group Inab phenotype.

An additional decay-accelerating factor (DAF) mutation, designated as Inab phenotype in the Cromer blood group system, was recently identified in a 28-year-old Japanese woman (H.A.). The red blood cells of H.A., like those of other Inab phenotype individuals, were negative for Cromer system antigens, Cra, Tca, Dra, UMC, and IFC. The deficiency of DAF on the red blood cells of H.A. has been shown by immunoblotting with a murine monoclonal antibody to DAF. Molecular analysis has shown that H.A. is homozygous for a single nucleotide substitution, C1579-->A, at the position 24 bp upstream of the 3'-end of exon 2 of the DAF gene. This substitution causes the activation of a novel cryptic splice site and results in the production of mRNA with a 26 bp deletion. The deletion introduces a reading frame shift and creates a stop codon immediately downstream of the deletion. Translation of mRNA would be terminated at the first amino acid residue of the second short consensus repeat (SCR2) domain (exon 3) of DAF. The functional domains of DAF's complement regulatory activity and the carboxy-terminal signal domains for glycosylphosphatidylinositol (GPI) anchoring are predicted to be lacking in H.A. Thus, there would be no DAF present on the cell surface.

Adult↗
PubMed1998

The natural history of an HLA haplotype and its recombinants.

The presence of haplotype-specific recombination sites can be determined by analyzing the conservation of extended haplotypes in the population. This approach considers all meioses in the history of the population and requires the presence of characteristic markers that easily allow the identification of the haplotype or of its recombined segments. The recombination breakpoint can then be mapped by looking for shared alleles between haplotypes selected through the specific marker/s. We identified a rare perfect tandem duplication of a 145 base pair segment in the LTA promoter, which tags a B60 (B60D) haplotype. The duplication was detected in 16/90 B60+ Europeans, while absent in 101 B60+ Orientals. The conservation of the class I end and the extreme variability of the class II end suggested that the present-day B60D haplotypes originated from an ancestral haplotype by recombination events centromeric to the duplicated sequence. Through a fine mapping using markers of the HLA central region a preferential recombination site was localized in the 60 kilobase interval between TNFd,e, and D6S273/K11 Amicrosatellite loci (i.e., between LST1 and BAT3 genes). This site behaves as a potent recombination enhancer leading to fragmentation in most of the extant B60D haplotypes and can be considered responsible for their "instability". In the relatively recently founded Finnish population, where the LST1/BAT3 interval recombination has probably not yet had the chance to occur, a founder effect can explain the presence of a rare DP (DPB1(*)1601) allele in most B60D haplotypes in this population.

Base Sequence↗
PubMed1998

Gene arrangement of the killer cell inhibitory receptor family on human chromosome 19q13.4 detected by fiber-FISH.

Human chromosome 19q13.4 has recently been revealed to be a remarkable region harboring multiple receptor genes of the immunoglobulin (Ig) superfamily differentially expressed on hematopoietic cell lineages. Over the past few years, more than 50 cDNAs have been cloned for the natural killer cell inhibitory receptor (KIR) gene family, which possess two or three Ig-like domains in the extracellular region. In this study, using two genomic DNA probes containing intron sequences of genes corresponding to the two- and three-domain types, we applied two-color-fluorescence in situ hybridization on stretched DNA fiber preparations (fiber-FISH). As a result, 11 positions homologous to KIR genes were found as a cluster within a range of approximately 120 kilobases on a chromatin fiber from human chromosome 19.

Chromosome Mapping↗
PubMed1998

Analysis of HLA class II and TAP alleles in Japanese patients with psoriasis vulgaris.

We investigated HLA class II and transporter associated with antigen processing (TAP) alleles in eighty-five unrelated Japanese patients with psoriasis vulgaris and fifty-two healthy controls using the polymerase chain reaction-restriction fragment length polymorphism method. The frequencies of DRB1*1502 and DQB1*0601 were increased in the patient group (DRB1*1502; 21% vs 12%, p < 0.05, DQB1*0601; 35% vs. 21%, p < 0.05), while the frequencies of DRB1*0406 and TAP2*E were decreased in the patients (DRB1*0406; 2% vs 9%, p < 0.05, TAP2*E; 4% vs 11%, p < 0.05). However, none of these remained significant after p values were corrected for the number of comparisons made (pc > 0.05). We also analysed specific amino acids on HLA class II molecules, but no significant difference was found between the two groups. Our previous reports clarified that aspartate at residue 9 (48% vs 20%, p < 0.002) and alanine at residue 73 (81% vs 48%, p < 0.0001) on HLA-C molecules were strongly associated with Japanese patients with PsV. These specific amino acids on HLA-C molecules are supposed to play more important roles compared with HLA class II and TAP alleles in the development of psoriasis vulgaris.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1998

A nested PCR-RFLP method for high-resolution typing of HLA-A alleles.

We developed a nested polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) method for high-resolution typing of HLA-A alleles. HLA-A alleles can be identified by this method without the need for other information such as serological type. The first PCR was performed using outer primers, ASP5 and ASP3, specific for the HLA-A gene, and a 991-bp DNA fragment extending from exon 1 through exon 3 was amplified. In the second PCRs, exon 2 and exon 3 of the HLA-A gene were amplified separately from the diluted first PCR product using nested primers. Computer analysis of cleavage patterns for 78 HLA-A alleles showed that 31 RFLP patterns could be obtained by digestion of the exon 2 PCR product using eight restriction endonucleases and 42 RFLP patterns by digestion of the exon 3 PCR product using 11 restriction endonucleases, and all alleles could be discriminated based on combinations of these RFLP patterns except for nine allele groups or pairs: A*0201/0207/0215N/0220/0222, A*0205/0208/0214, A*0206/0221, A*0212/0213, A*2402/2405, A*2406/2413, A*2601/2605, A*2603/2606 and A*7401/7402. Thus, 65 PCR-RFLP patterns were predicted from the results of analysis of digestion patterns of 78 HLA-A alleles. Among 2145 possible homozygous and heterozygous combinations of the 65 distinguishable PCR-RFLP patterns, 82 combinations were predicted to have the same PCR-RFLP patterns. In PCR-RFLP analysis, although the nested primers were not specific for the HLA-A gene, clear RFLP banding patterns were obtained because specificity was guaranteed by the use of the outer primers, ASPS and ASP3 in the first PCR. A*0201 and A*0207 occur relatively frequently in the Asian populations among indistinguishable allele groups or pairs using the present PCR-RFLP method. We also developed a PCR sequence-specific primers (PCR-SSP) method for distinguishing between A*0201/0220/0222 and A*0207/0215N. We could identify 39 alleles (groups) upon HLA-A typing of 50 Japanese individuals, 40 cell lines of the Fourth Asia-Oceania Histocompatibility Workshop, and 80 cell lines of the UCLA International Cell Exchange Program using the present PCR-RFLP and PCR-SSP methods.

Alleles↗
PubMed1998

Immunosuppressive effects of chloroquine: potential effectiveness for treatment of post-transfusion graft-versus-host disease.

Post-transfusion graft-versus-host disease (PT-GVHD) is a fatal adverse effect of blood transfusion. In spite of its severity, there is no effective treatment at present for PT-GVHD. Previously, we reported that chloroquine (CH) inhibited the cytotoxicity of cytotoxic T-cell (CTL) clones and tumour necrosis factor beta (TNF beta) production by TNF beta-producing clones in vitro, both the clones being derived from peripheral blood lymphocytes (PBMCs) of PT-GVHD patients. To explore the possibility of utilizing CH for the treatment of PT-GVHD, we extended our investigation of the immunosuppressive effects of CH in vitro to PBMCs derived from healthy donors. Our results show that CH inhibits the mixed lymphocyte reaction (MLR) between allogeneic PBMCs, production of inflammatory cytokines such as TNF alpha, interleukin-1 beta (IL-1 beta) and interferon gamma (IFN gamma) in mixed lymphocyte culture and natural killer cell activity, and, further, reduces the number of alloreactive CTL precursors.

Chloroquine↗
PubMed1998

Construction of mono- and bivalent human single-chain Fv fragments against the D antigen in the Rh blood group: multimerization effect on cell agglutination and application to blood typing.

An expression system for mono- and bivalent single-chain Fv fragments (scFv) of a human antibody against D antigen in the Rh blood group system was established in Escherichia coli. The cDNA encoding the Fv fragment of the anti-D monoclonal antibody D10 was cloned using the polymerase chain reaction and expressed in E.coli by fusing with a peptide tag link in the C-terminus of the light chain variable region. The scFv fragment expressed by the bacteria produced specific agglutination of human D positive red cells in the presence of an anti-peptide tag antibody. Flow cytometric analysis clearly indicated that the bacterially prepared scFv showed high specificity and affinity for D antigen, which was identical with that of the parental IgG. In order to construct bivalent D10 scFv for use in direct cell agglutination, the scFv was fused with a dimeric protein, bacterial alkaline phosphatase (BAP). The fusion protein produced significant agglutination of human red blood cells with D antigen, confirming that the bacterially expressed fusion protein is a functional bivalent antibody fragment. Specific agglutination of D positive red cells by D10 scFv-BAP was enhanced in the presence of anti-BAP antibody, suggesting that further multimerization of scFv led to highly efficient cell agglutination. By grafting BAP enzymatic activity into the scFv fragment (enzyme-linked scFv), blood typing could conveniently be performed. These results indicate that bacterially expressed scFv and scFv-BAP would be of practical use in blood typing. The system reported here could also be applied to the examination of other cell surface antigens and cell agglutination.

Alkaline Phosphatase↗
PubMed1998

HLA haplotypes in Koreans based on 107 families.

There are marked differences in the distribution of HLA haplotypes among different populations, and multilocus HLA haplotypes can best be studied by family analysis. In the present study, 107 Korean families were analyzed for HLA-A, B, C, DR, and DQ antigens and haplotypes. Allele frequencies of more than 10% for class I antigens were A2, A24, A33, B44, B62, Cwl, Cw7, Cw9, Cw10, and C blank (CBL) and those for class II antigens were DR4, DR8, DR13, DR15, DQ1, DQ3, DQ4 and DQ7. In the analysis of HLA haplotypes, 18 kinds of A-B-DR and 11 kinds of A-C-B-DR-DQ haplotypes occurred at frequencies of more than 1%, comprising 34% and 24% of the total theoretical haplotypes, respectively. The five most common A-B-DR haplotypes were exclusively related with the five most common A-C-B-DR-DQ haplotypes (frequency>2%). These remarkably conserved five-locus haplotypes in Koreans were A33-CBL-B44-DR13-DQ1 (5.4%), A24-Cw7-B7-DR1-DQ1 (3.5%), A33-Cw7-B44-DR7-DQ2 (3.0%), A33-Cw10-B58-DR13-DQ1 (2.3%), and A30-Cw6-B13-DR7-DQ2 (2.3%). Comparison of the distribution of A-B-DR haplotypes among East Asian populations revealed that Koreans are closest to Japanese, but show a higher degree of polymorphism in the distribution of HLA haplotypes compared to Japanese. The results obtained in this study will be useful as basic data on Koreans for anthropology and organ transplantation.

Alleles↗
PubMed1998

Diversity of HLA-B61 alleles and haplotypes in East Asians and Spanish Gypsies.

The distribution of HLA-B61 alleles and their association with HLA-C and DRB1 alleles were investigated in six East Asian populations (South Korean, Chinese Korean, Man (Manchu), Northern Han, Mongolian and Buryat) and Spanish Gypsies and compared to our previous report on the Japanese population. The alleles were identified using a group-specific polymerase chain reaction (PCR) and genomic DNA followed by hybridization with sequence-specific oligonucleotide probes (SSOP). Both HLA-B*4002 and B*4006 were commonly detected in the South Korean, Chinese Korean, Man, Northern Han and Japanese populations, while HLA-B*4002 was predominant in the Mongolian and Buryat populations. Strong associations of B*4002 with Cw*0304 and of B*4006 with Cw*0801 were commonly observed in these East Asian populations. In contrast, in Spanish Gypsies, only HLA-B*4006 was found and the allele exhibited a strong association with Cw*1502. HLA-B*4003 was also identified in the South Korean, Chinese Korean, Northern Han, Mongolian and Japanese populations at relatively low frequencies, and exhibited an association with Cw*0304. Moreover, the association of these B61 alleles with the DRB1 alleles revealed considerable diversity among the different populations. HLA-B*4004 and B*4009 were not observed in these populations. Consequently, the frequencies of the B61 alleles varied among the different East Asian populations, but the individual B61 alleles were carried by specific haplotypes often regardless of the ethnic differences.

Alleles↗
PubMed1998

Polymorphism of TAPASIN and its linkage disequilibria with HLA class II genes in the Japanese population.

Tapasin plays an important role in HLA class I assembly. The gene has been mapped on the human MHC region. We identified two alleles of TAPASIN in the Japanese population and analyzed the association of the alleles with HLA-DPB1, -DQB1 and -DRB1 alleles. The allele frequencies of TAPASIN*01 and *02 were estimated to be 0.37 and 0.63, respectively, in the Japanese population. TAPASIN showed strong linkage disequilibrium with the HLA-DPB1 locus. Several frequent four-locus haplotypes were identified, including DRB1*0901-DQB1*0303-DPB1*0501-TAPASIN*02, DRB1*0901-DQB1*0303-DPB1*0201-TAPASIN*02 and DRB1*1302-DQB1*0604-DPB1*0401-TAPASIN*02.

Antiporters↗
PubMed1998

Human lymphocytes obtained from decidual tissue express killer activatory receptors as well as killer inhibitory receptors: analysis using a single strand conformation polymorphism method.

PROBLEM: The objective was to clarify whether lymphocytes in decidual tissue express only killer inhibitory receptors (KIRs) or both KIRs and killer activatory receptors (KARs). METHOD OF STUDY: A polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis method, using cDNA as a template, was applied to detect as many natural killer receptors (NKRs) expressed on natural killer (NK) cells as possible and to distinguish between KIRs and KARs. Using this method, we analyzed NKRs on lymphocytes in decidual tissue and maternal peripheral blood mononuclear cells (PBMCs) (n = 10) from the same individuals. RESULTS: More than 20 SSCP bands were detected for NKRs on both the lymphocytes in decidual tissue and the maternal PBMCs. The SSCP band patterns were different for each individual. KARs mRNA was detected in lymphocytes in decidual tissue according to the SSCP analysis results. CONCLUSION: Lymphocytes in decidual tissue express not only KIRs but also KARs; this finding suggests their roles in placentation and the maintenance of pregnancy.

Abortion, Induced↗
PubMed1998

Differential effect of azidothymidine on resting and activated cells: potentiality of this drug for treatment of post-transfusion graft-versus-host disease.

The key factor for the treatment of post-transfusion graft-versus-host disease (PT-GVHD) is the successful eradication of donor-derived cytotoxic T cells (CTLs) which are thought to be a main cause of the disease, with no effects on either peripheral blood mononuclear cells (PBMCs) or tissues of the recipient. In this study, we examined the effect of azidothymidine (AZT: Zidovudine) on resting PBMCs and cultured fibroblast cells which are assumed to be patient cells, and alloreactive CD8(+)-CTL clones which are imagined to be donor-derived activated CTLs, in vitro. We show here that AZT has no effect on resting PBMCs and cultured fibroblast cells, but greatly inhibited the growth of CTL clones.

Anti-HIV Agents↗
PubMed1998

Different alleles cause an imbalance in A2 and A2B phenotypes of the ABO blood group.

BACKGROUND AND OBJECTIVES: In several populations, including the Japanese, the frequency of the A2B phenotype is significantly higher than expected based on the A2 phenotype frequency. To understand the genetic basis of this 'excess' of A2B, we examined ABO alleles in individuals with A2-related phenotypes. MATERIALS AND METHODS: ABO alleles were identified by means of polymerase chain reaction single-strand conformation polymorphism (SSCP) and nucleotide sequence analyses. RESULTS: The frequencies of A2-related alleles (*A105, *A106, *A107, *A111 and *R101) were clearly different between the A2 and A2B phenotypes. In particular, a putative recombinant allele, *R101, was uncommon in the A2 but common in the A2B phenotype individuals. This allele was also detected in 4 of 401 (1%) unrelated A1 phenotype (AO genotype) individuals. CONCLUSION: *R101 is presumably expressed as phenotype A1 in *R101/*O heterozygous individuals, but as phenotype A2 in *R101/*B heterozygotes, thus giving rise to a high A2B phenotype frequency.

ABO Blood-Group System↗
PubMed1998

[Standardization of hemopoietic colony assay reagents].

Several Japanese Red Cross blood centers have begun cooperating with hospitals in peripheral blood stem cell transplantation research. However, most have not yet standardized their techniques or reagents for that purpose yet. Consequently, wide variations are often observed in data from different blood centers, especially for hemopoietic colony assays. We compared our colony assay reagent set with those in three commercial colony assay kits. The best results were obtained with the kit from a manufacturer referred to here as company A. Although our reagent set obtained lower colony values, the CFU-GM, BFU-E, and total colony values correlated well with those obtained using company A's kit (r = 0.74, 0.80, and 0.97, respectively). Company A's kit gave reproducible results even with the use of different lots, and includes reagents that can be stored for up to two years at -20 degrees C. These features highlighted its advantages as a standard reagent set.

Colony-Forming Units Assay↗